1. Technical Field
The present invention relates to a method and system for data processing in general, and in particular to a method and system for processing video data within a data processing system. Still more particularly, the present invention relates to a method and system for compressing color video data within a data processing system.
2. Description of the Prior Art
Full-motion video displays based upon analog video signals have long been available in the form of television. With recent improvements in digital is processing capabilities and affordability, full-motion video displays based upon digital video signals are becoming more widely available. Digital video systems can provide significant improvements over their analog counterparts in generating, modifying, transmitting, storing, and playing full-motion video sequences. With digital video systems, each image frame is a still image formed from an array of pixels according to the display resolution of a particular system. The display resolution of digital video systems can range from 640xc3x97484 pixels for NTSC based VHS systems to 1280xc3x97720 pixels for high-definition television (HDTV) systems.
One problem with digital video systems is that the amount of raw digital information included within video sequences are massive. As an example, a full-length motion picture of two hours in duration in a digitized form of a relatively low resolution VHS image format having a 640xc3x97484 pixel resolution could correspond to over 100 gigabytes of digital video information. In response to the limitations in storing or transmitting such massive amounts of digital video information, various video compression standards, such as MPEG-1, MPEG-2, H.26X, etc., have been established. The techniques utilized by these video compression standards are typically based upon the similarities between successive image frames, referred to as temporal or interframe correlation, to provide interframe compression in which pixel-based representations of image frames are converted to motion representations. In addition, some video compression standards utilize similarities within image frames, referred to as spatial or intraframe correlation, to provide intraframe compression in which the motion representations within an image frame are further compressed. Although most video compression standards can typically provide an adequate video compression ratio, it would be desirable to provide an improved digital compression algorithm for compressing color video data.
In accordance with a preferred embodiment of the present invention, a pixel, which includes multiple bits that forms a color value, is initially received. A determination is made as to whether or not the color value of the pixel falls within a predetermined tolerance range. If the color value of the pixel falls within the predetermined tolerance range, then a single-bit true signal is sent to a compressor. Otherwise, if the color value of the pixel does not fall within the predetermined tolerance range, then the entire color value of the pixel is sent to the compressor.
All objects, features, and advantages of the present invention will become apparent in the following detailed written description.